Furnace draft apparatus.



No. 823,396. PATENTED JUNE 12, 1906. W. N. 00X. PURNAGE DRAFT APPARATUS.

APPLICATION FILED AUG.15.1904.

2 SHEETS-SHEET 1.

'PATENTBD JUNE 12, 1906.

APPLICATION FILED AUG.15.1904.

2 SHEETS-SHEET 2.

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NITED STATES PATENT onirica.

WILLIAM N. COX, OF MONTGOMERY, ALABAMA, ASSIGNOR TO THE MOONEY DEVELOPMENT CO., A CORPORATION OF NEW JERSEY.

Specification of Letters Patent.

Patented June 12, 1906.

Application iiledbAugust 15,1904. Serial No. 220,813.

To all whom it may concern:

Be it known that I, WILLIAM N. Cox, a citizen of the United States, residing at Montgomery, in the county of Montgomery and State of Alabama, have invented certain new and useful Improvements in Furnace Draft with a fire-box and a hollow bridge-wall therefor, an air-supply pipe discharging into said bridge-wall, means for directing air from one.

end of said pipe into said bridge-wall, means for leading air from the said end of the pipe to the opposite end thereof and for directing air into said opposite end and thence into the bridge-wall, and means for supplying the air admitted to the bridge-wall to the products of combustion rising from said fire-box.

. The invention comprises certain other novel-constructions, arrangements, and combinations of parts, as will be hereinafter fully p described and claimed.

In the accompanying drawings, Figure 1 represents a longitudinal vertical central section taken through a furnace embodying the features of the resent invention, parts being illustrated in e evation. Fig. 2 represents a perspective view of a part of the heater and air-supply pipe illustrated as removed from the casing. Fig. 3 represents an enlarged detail, in front elevation,. of a part of the header. Fig. 3EL represents an edge view of the same, parts being shown in section. Fig. 3b represents a transverse vertical section taken on the plane of line 3b 3b of Fig. 3. Fig. 4 represents a longitudinal section vtaken on the plane of line 4 4 of Fig. 3. Fig. 5 represents a detailed fragmentary sectional view of the central portion of the air-supply pipe, illustrating the nozzle thereof.

Referring to the drawings by numerals, 1

l indicates any suitable masonry-work or other casing for a boiler-furnace, the present invention being illustrated as applied to a boiler-furnace, it being understood that the same is applicable to any type of furnace.

Mounted within the casing 1 is a boiler 2, sup orted in the usual manner at the sides an resting centrally upon a hollow bridgewall 3. The hollow bridge-wall 3 divides the casing 1 beneath the boiler into a heat-chamber 4 in the rear and a fire-box 5 in the front, said fire-box being provided with the usual form of grate 6 or other devices found desirable. Extending transversely through the bridge-wall 3 at a point near the upper edge thereof are draft-eyes 7, communicating between the fire-box 5 and the heat-chamber 4, any preferred number of said draft-eyes being employed and each of the same being provided with series of apertures 8 8, communicating vwith the space between the sections of the hollow bridge-wall 3, so that air injected into said space will be free to move into the said draft-eyes and there to commingle with the products of combustion rising from the grate 6.

An air-supply pipe 9 extends from the rear of the casing 1 throughout the length thereof to the front of said casing, and said pipe is preferably disposed at one side of the casing and is provided intermediate its length with a discharge-nozzle 10, directed into the space between the sections of the hollow bridgewall 3. The portion of pipe 9 extending past fire-box 5 is of course positioned outside the fire-brick of said box, and therefore I have illustrated said ortion of pi e 9 in dotted lines in Fig. 1. ere it is to e noted that a pipe 9 may be arranged at each side of the casing 1 instead of at one side, if desired. The air-supply pipe 9 is provided with a branch pipe 9', which extends from the pilpe 9 at a oint in the rear of the bridge-wal 8 and is fJed upwardly about the boiler 2, longitudinally of the same along the up er edge thereof, and downwardlyin front of t eboiler for pur oses hereinafter mentioned.

At t e front of the casing 1 is arranged a header, generally referred to by the numeral 11, said header comprising a relatively large tube 12, communicating with the front end of .the supply-pipe 9 and arched over the usual furnace-doors 13, opening into the firebox 5. J ust in rear of the tube l2 is arranged a steam-pipe 14, which may be formed integral with the tube l2 and the web 15 inter- 1 posed between said pipe and tube for dividing the same. The steam-pipe 14 extends throughout the length of the arch formed by pipe 9 said pipe 14 communicates with a' steam-supply pipe 1 5, leading from the steamdome 16 of the boiler 2. Leading from the tube 12 into the fire-box 5 are suitable discharge-nozzles 16 16, and discharging into each of said discharge-nozzles is an injectornozzle 17, leading from the pipe 14 and extending across the tube 12 into the respective nozzle 16. A needle-valve 18 is preferably employed with each ofthe nozzles 17 for controlling the amount of steam flowing through said nozzle. The header 11 is thus made up' of an arch formed of an air-supply tube and a steam-pipe with nozzles for'permitting the injection of air by suction produced by the discharge of steam throughsuch nozzles, and said header may be supplied with steam and air at one end only, as illustrated, or, if preferred, as above suggested, a pipe 9 may be arranged at each side ofthe casing 1, in which case air would be supplied to the tube 12 at each end of a pipe 9 leading from each of the'p'ipes 9, and the pipe 14 might also be supplied with steam at each end. An even distribution of pressure `could thus be very readily maintained, and, if desired, the header m'ightbe'divided into two sectionsby a partition arranged centrally of the arch. Of course all of these features are within they scope and spirit ofthe present invention and may ormay not be employed, as preferred.

A nozzle 19, similar in construction and arrangement to the nozzles 16,` extends inwardly from tube 12 at the end'communieating with the front end of the pipe- 9" and projects longitudinally into the front end 'oi the pipe 9', and a nozzle 20, similar to nozzles 17, is arranged for discharging steam into the nozzle 19', controlled b'y a suitable needlevalve 21, so that in operation when thevalve 21 is opened steam passing through the nozzle 2'0 produces suction in the nozzle 19 and causes a discharge of air drawn through pipe 9 and branch pipe 9 the said discharge of 'air passing inwardly longitudinally of the pipe 9 until arriving at a point of the nozzle 10 'of said pipe 9. At this point is arranged a bafile-plate 22, which extends transversely of the pipe 9` entirely across the same for" a slight distance into the nozzle 10, so that air moving in through the pipe 9 under the pressure of steam discharged from nozzle 20 will be deflected and discharged out of nozzle 10, as indicated by the arrows in Fig. 5. This dischargedjair will of course produce a certain amount of draft within the rear portion of the pipe 9 and will cause such air within the said pipe as is not drawn through pipe 9 to' move out through the nozzle 10, as indicated by the arrows in said Fig. 5.

`For the purpose of effectively controlling the precise amount of air discharged into the yfurnace I contemplate employingfa valve at the rear end of the pipe 9 for controlling the amount of air entering said pipe. Said valve is seen in Fig. 1 of the drawings and consists simply of a conical body 23, having its longitudinal axis in line with the longitudinal axis of the pipe 9. The valve-body 23 is preferably provided with eyes 25, surrounding guiding-bars 26 2 6, projecting rearwardly from the end of the pipel 9. One or both yof said eyes 25k may be provided vwith a setscrew 27, adapted to be Atightened upon the respective bar 26 for locking the valvel in the given position. The valve-body 23 may thus be caused to enter the end of the pipe 9 and be locked in any desired position, even to the extent of being moved Vinto contact with the end of the pipe forcompletely closing said end, or'the valve-body may be moved rearwardly entirely outside of the pipe.

In operation the valves 17 and valve 21 may be set at any given position and the supply of steam to pipe 14y controlled inv any `preferred manner, orthe valves 17 and valve 21 may be operated for-controlling the discharge of steam, and when it isdesired to ysupply heated air toI theproducts of combustion within the` fire-box and the heatingchamber it is only` necessary when the valves 17and valve 21 are 'opento admit steam to pipe 14, whereupon, assuming the valveV 23 to be open, the discharge of 'steam through noz-` zles 16' willlcause air to be drawnv into the rear end of pipe 9, up through branch pipe 9about the arched tube 12,l and into theii'rebox, and the'discharge of steam through no'zv zle' 19 will cause a' similar 4intake of air and the discharge' ofsame,l longitudinally rearward through they frontportion of pipe 9 and out of nozzle 10, the discharge through nozzle4 10 effecting a draft in the pipe- 9 past thel branch pipej9 and causing a certain amount of air withinthe pipe 9 to -move outof nozzle 10 without having first been drawn `up through pipe 9. The air discharged between the parts'of the hollow bridge-wall 3 will its way out through the `aperturesl 8 into the several 'draft-eyes 7 and be consumed while aidingv in the support of combustion.

The pipe 9 is passed about theboiler in the manner described for'the purpose offurther heating the airl which ispassed through pipe 9", and said pipe V9y may therefore lbe positioned in any desired manner within the casin@r 1 atthe points mosti advantageousfor su jecting same to thel greatest'number of heated units, whereby the atmosphere directed into the hre-box a-nd-suppliedto` the draft-eyes will possess a lmaximum temperature and will nothave a chill-ingeffectupon he products ofcombustion within the ire- IOO IIO

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent of the United States, is

l. In a draft a paratus, the combination with a furnace inc osure, of a pi e extending therethrough and provided wit an opening intermediate its length for supplying air to the interior of said inclosure, a branch pipe between the air-inlet and the discharge-opening leading from said first-mentioned pipe, a nozzle in communication with said branch pipe and extending longitudinally of said Erst-mentioned pipe beyond the dischargeo ening, a pressure-Huid injector discharging t ough said nozzle, and a baffle arranged in said first-mentioned pipe opposite the discharge-opening thereof.

2. n a draft apparatus, the combination with a furnace inclosure, of a ipe for supplying air to the interior thereof,}Ixaving one end exposed to the atmosphere, a conical valvebody disposed with its longitudinal axis in line with the longitudinal axis of said pipe, eyes carried by said body, and guiding-rods supporting said eyes for maintaining said va ve in various positions with respect to the exposed end of said pipe for controlling the amount of air entering the same.

3. In a furnace draft apparatus, the combination with a furnace inclosure, and a header arranged at the front thereof, of an airsupply pipe leading from the atmosphere t ough said inclosure to the header, and having an opening intermediate its length discharging into said linclosure, a branch pipe leading from the air-su ply pipe at a point between the inlet and t e discharge-opening and extending to and communicatin with the header, nozzles leading from the eader into said furnace inclosure, a nozzle leading from said header into the air-supply pipe, means for supplying a pressure fluid to said nozzles for producing a ow of air from the branch pipe through said nozzles, and means in said air-supply pi e for directing the air discharged through thle nozzle extending into said pipe through the discharge-opening therein.

4. In a furnace draft apparatus, the combination with a furnace inclosure, of an airsupply pipe extending into the same and formed with a discharge-opening intermediate its length, one end of said air-supply pipe being exposed to the atmosphere and t e other bein closed, a baflie arranged in said pipe opposlte the discharge-opening, a branch pipe leading from the air-supply pipe at a point between the exposed end and the baffle and extending to a point for being heated and communicating with the said air-supply pipe at a point beyond the baffle, and for creating a flow of air through said branch air-pipe and into said air-supply pipe for causing the air to be delivered against said baffle and to be directed thereby out the said discharge-opening.

5. In a furnace air-feeding mechanism, the combination with a furnace inclosure, of an air-supply pipe extending into said furnace from the rear thereof, the rear end of said pipe being exposed to the atmosphere, said pipe being provided with a discharge-opening intermediate its length for delivering air into the furnace inclosure, a baflle arranged Within said air-supply pipe for preventing air from passing longitudinally of the pipe beyond the discharge-opening therein, and for directing air moving within said pipe through said opening, a branch pipe leading from said air-supply pipe at a point between said baffle and the open end of the pipe and extending to a point for being heated, and means for directing air under pressure from said branch pipe into that portion of the said air-supply pipe extending forwardly of the baffle.

In testimony whereof I afiix my signature in presence of two witnesses.

WILLIAM N. COX.

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